You Have Deployed a Three-Tier Web Application in a VPC

question 491

Multiple Choice

You have deployed a three-tier web application in a VPC with a CIDR block of 10.0.0.0/28. You initially deploy two web servers, two application servers, two database servers and one NAT instance tor a total of seven EC2 instances. The web, application and database servers are deployed across two availability zones (AZs) . You also deploy an ELB in front of the two web servers, and use Route53 for DNS Web (raffle gradually increases in the first few days following the deployment, so you attempt to double the number of instances in each tier of the application to handle the new load unfortunately some of these new instances fail to launch. Which of the following could be the root caused? (Choose 2 answers)

• A) AWS reserves the first and the last private IP address in each subnet's CIDR block so you do not have enough addresses left to launch all of the new EC2 instances
• B) The Internet Gateway (IGW) of your VPC has scaled-up, adding more instances to handle the traffic spike, reducing the number of available private IP addresses for new instance launches
• C) The ELB has scaled-up, adding more instances to handle the traffic spike, reducing the number of available private IP addresses for new instance launches
• D) AWS reserves one IP address in each subnet's CIDR block for Route53 so you do not have enough addresses left to launch all of the new EC2 instances
• E) AWS reserves the first four and the last IP address in each subnet's CIDR block so you do not have enough addresses left to launch all of the new EC2 instances

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Definitions:

Periodic Inventory System

An inventory accounting method where inventory levels are updated and physical counts are conducted at specific intervals.

Ending Inventory

The total value of goods available for sale at the end of an accounting period, calculated by adding purchases to the beginning inventory and subtracting the cost of goods sold.

FIFO

An inventory valuation method standing for "First-In, First-Out," where goods purchased or produced first are sold or used first.

Gross Profit

The difference between sales revenue and the cost of goods sold before administrative and other expenses are deducted.